Well since FireFox has gotten alot of users, the crackers are focusing on creating exploits for it, and I've already noticed that many "Pop-Unders" aren't blocked by FireFox. And mannnnnn they are annoying. Thats why now more people are switching to Opera, as it has a sleek user interface, and well is underground so there arent many exploits for it. You don't get any popups or popunders on it. I can't go without firefox's extensions and themes, only reason that I'm still on it.